A serious reply though -
The Sony MDRNC50's are the most isolating headphone I've found. They are noise cancelling, plus they have the "around the ear" design that blocks out a decent amount of the rest of the noise. I remember them being pretty comfortable, although I found the sound quality to be crap - it was just dead and lifeless. But it wasn't screetching or anything - you could give them a try yourself (or, uhm, your friend could
). They sell them at any best buy, amazon.com, compusa, etc etc for anywhere between $120 and $200.
The BOSE noise cancelling headphones might an ok compromise between isolation and sound quality. They're $300, but I do think they sound better than the Sony's. I'm afraid I can't compare their noise isolation, as I don't have two pairs to compare, but they both have the same basic external design. A lot of people on this forum don't like BOSE, but no one's been able to suggest anything with equivalent/better noise reduction overall that sounds better (The Senn 250 has pretty good sound. Unfortunately, they suck at noise cancellation - I have a pair that I've been using for the last several months, so I know).
If you're *REALLY* *REALLY* serious about reducing noise, I bet for about a grand these would really do the trick:
http://www.bose.com/controller?event..._headset_index
Lastly, someone posted a pdf with a huge list of the non-noise-cancelling closed headphones a few ago, but I've spent 15 minutes trying to find it and I just can't seem to. (With my luck, it's probably posted on a sticky that I've missed several times). "markl" wrote the pdf, so maybe someone else knows the link to it...the pdf actually had a table of the noise isolation he thought each headphone had.
Hope you write back what ends up working for you...uhm, I mean you friend.